It would be necessary for us to know where you are located.
Your plants should certainly flower the next season providing you take the necessary
steps to protect from freezing if applicable.
Kent

I know from Zone 8 and higher, cannas can stay usually stay in ground. However, the leaves die back from frost. Being perennial and if they were well watered and received enough sun in the previous year, though, they will return in even greater numbers each subsequent year.